Amorphous alloy material

ABSTRACT

An amorphous alloy material is provided, including 55%˜65% iron, 10%˜20% cobalt, 13%˜17% silicon, 8%˜12% boron and unavoidable impurity in weight percentage. The amorphous alloy material has good soft magnetic performance.

TECHNICAL FIELD

The disclosure relates to an amorphous alloy material, and more particularly, to an amorphous alloy material having good soft magnetic performance.

BACKGROUND

Wireless charging technology is the application trend in future electronic products, wherein magnetic resonance wireless charging technology requiring an iron core has advantages such as one-to-many and long charging distance, and chargers for various electronic products can be integrated, such that the effects of reducing electronic waste and reducing environmental burden are achieved.

The material currently used in magnetic resonance wireless charging technology is silicon steel sheet which is a metal alloy soft magnetic material having characteristics such as magnetic flux, permeability, and iron loss. However, the iron loss of the silicon steel sheet is the main reason that conversion efficiency cannot be increased, resulting in a bottleneck for magnetic resonance wireless charging technology research and development. Therefore, a material having better magnetic properties than silicon steel sheet is urgently needed. Due to the drawbacks of the silicon steel sheet, a potential material in development is the metallic glass soft magnetic material having better magnetic permeability (3 to 5 times that of the silicon steel sheet) and iron loss (only 1/7 or less than the silicon steel sheet). However, the glass-forming capability of the known iron-silicon-boron material is too low and the demand for the cooling rate in the process is too high, such that difficult processing occurs, and therefore a thinner soft magnetic material having different shapes cannot be readily designed for the present charging device.

Based on the above, the development of a material more suitable for wireless charging technology to alleviate the drawbacks of the known silicon steel sheet and metallic glass soft magnetic material is an important topic in the art.

SUMMARY

The disclosure provides an amorphous alloy material having good soft magnetic performance to improve the drawbacks of known silicon steel sheets and metallic glass soft magnetic materials, so as to be better applied in wireless charging technology.

The amorphous alloy material of the disclosure includes 55%˜65% iron, 10%˜20% cobalt, 13%˜17% silicon, 8%˜12% boron and unavoidable impurity in weight percentage.

In an embodiment of the disclosure, the amorphous alloy material has a glass transition temperature T_(g)>800K, a simplified glass transition temperature T_(g)/T_(l)>0.56, a saturation magnetic flux density >1.45 T, and a coercive force <0.8 O_(e).

The amorphous alloy material of the disclosure is composed of the following element and ratio: 55%˜65% iron, 10%˜20% cobalt, 13%˜17% silicon, 8%˜12% boron and unavoidable impurity in weight percentage.

In an embodiment of the disclosure, the amorphous alloy material has a glass transition temperature T_(g)>800K, a simplified glass transition temperature T_(g)/T_(l)>0.56, a saturation magnetic flux density >1.45 T, and a coercive force <0.8 O_(e).

Based on the above, the disclosure provides an amorphous alloy material containing a cobalt element, and via the iron element, cobalt element, silicon element, and boron element therein, the amorphous alloy material has better glass-forming capability and coercive force, and the soft magnetic performance thereof can be further increased in terms of material characteristics. Moreover, the amorphous alloy material of the disclosure has better heat resistance, and compared to the known amorphous alloy material, has higher stability and is not readily crystallized when temperature is increased in the process.

Several exemplary embodiments accompanied with figures are described in detail below to further describe the disclosure in details.

DETAILED DESCRIPTION OF DISCLOSED EMBODIMENTS

The disclosure provides an amorphous alloy material including an iron element, a cobalt element, a silicon element, and a boron element. More specifically, the amorphous alloy material of the disclosure includes 55%˜65% iron, 10%˜20% cobalt, 13%˜17% silicon, 8%˜12% boron and unavoidable impurity in weight percentage, for instance.

For instance, the iron element, cobalt element, silicon element, and boron element are melted in a vacuum state to form an alloy, and then these elements are fully melted and mixed to form a mother alloy, and then the mother alloy block is turned into powder to complete the desired shape and morphology via, for instance, lamination. In addition, via the incorporated amorphous alloy element, the powder is more suitable for lamination in a subsequent process.

By mixing the iron element, cobalt element, silicon element, and boron element at specific atomic percents, the amorphous alloy material of the disclosure has better glass-forming capability (a block having a diameter of about 1.5 mm can be formed) and coercive force due to the addition of cobalt element in high melting point which increases the material entropy after mixing. As a result, soft magnetic performance can be further increased in terms of material characteristics, and the difficulty of forming in the subsequent process is reduced due to high glass-forming capability. Moreover, the amorphous alloy material of the disclosure has better heat stability and heat resistance due to higher glass transition temperature, and compared to the known amorphous alloy material, has higher stability and is not readily crystallized (irregular arrangement) during rapid cooling when temperature is increased in the process. More specifically, the amorphous alloy material of the disclosure the amorphous alloy material has a glass transition temperature T_(g)>800K, a simplified glass transition temperature T_(g)/T_(l)>0.56, a saturation magnetic flux density >1.45 T, and a coercive force <0.8 O_(e), for instance.

In the following, the amorphous alloy material of the disclosure is described in detail via an experimental example. However, the following experimental example is not intended to limit the disclosure.

EXPERIMENTAL EXAMPLE

To prove that the amorphous alloy material of the disclosure has better soft magnetic performance, an experimental example is provided.

EVALUATION OF MATERIAL CHARACTERISTICS

Material characteristics such as maximum magnetic flux, relative permeability, iron loss, glass transition temperature T_(g), simplified glass transition temperature T_(g)/T_(l), saturation magnetic flux density, and coercive force were measured for the amorphous alloy material of the disclosure and a general silicon steel and iron-based metallic glass. The measurement results are listed in Table 1 and Table 2. The measuring method of the material characteristics is known in the art and is therefore not repeated herein.

TABLE 1 Maximum Relative Iron loss Iron core material magnetic flux (T) permeability (W/kg) General silicon steel about 1.7 6000 to 10000 2.1 to 10.0 China Steel about 1.7 — 2.0 50CS290 Iron-based metallic 1.0 to 1.5 >30000 0.1 to 0.8 glass

TABLE 2 T_(g) (K) T_(l) (K) T_(g)/T_(l) J_(s) (T) H_(c) (O_(e)) Example 1 814 1423 0.572 1.52 0.5

Table 1 lists the material properties of the general silicon steel and iron-based metallic glass, and Table 2 lists the material properties of the amorphous alloy material of the disclosure, wherein Example 1 is the amorphous alloy material produced according to the element and proportion disclosed in the present disclosure. As shown in Table 1 and Table 2, the amorphous alloy material of the disclosure has higher saturation magnetic flux density and lower coercive force such that good magnetic properties are achieved and power-saving performance is increased as a result.

Moreover, the amorphous alloy material of the disclosure has higher simplified glass transition temperature T_(g)/T_(l), and therefore the free energy of the amorphous material is reduced, such that the amorphous material is more readily formed. Moreover, the amorphous alloy material of the disclosure has higher glass transition temperature, and therefore has better stability.

Based on the above, the disclosure provides an amorphous alloy material including a cobalt element, and via the iron element, cobalt element, silicon element, and boron element therein, the amorphous alloy material has better glass-forming capability and coercive force, and the soft magnetic performance can be further increased in terms of material characteristics. Moreover, the amorphous alloy material of the disclosure has better heat resistance, and compared to the known amorphous alloy material, has higher stability and is not readily crystallized when temperature is increased in the process. As a result, the amorphous alloy material of the disclosure can replace existing materials and be better applied in wireless charging technology. Moreover, the amorphous alloy material of the disclosure has effects such as higher performance and operating temperature reduction, and therefore not only can the added value of the application be indirectly increased, the amorphous alloy material of the disclosure can also be applied in more innovative products.

It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the disclosed embodiments without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the disclosure cover modifications and variations of this disclosure provided they fall within the scope of the following claims and their equivalents. 

What is claimed is:
 1. An amorphous alloy material, comprising: 55%˜65% iron, 10%˜20% cobalt, 13%˜17% silicon, 8%˜12% boron and unavoidable impurity in weight percentage.
 2. The amorphous alloy material of claim 1, having a glass transition temperature T_(g)>800K, a simplified glass transition temperature T_(g)/T_(l)>0.56, a saturation magnetic flux density >1.45 T, and a coercive force <0.8 O_(e).
 3. An amorphous alloy material, consisting of: 55%˜65% iron, 10%˜20% cobalt, 13%˜17% silicon, 8%˜12% boron and unavoidable impurity in weight percentage.
 4. The amorphous alloy material of claim 3, having a glass transition temperature T_(g)>800K, a simplified glass transition temperature T_(g)/T_(l)22 0.56, a saturation magnetic flux density >1.45 T, and a coercive force <0.8 O_(e). 